The basic law of technology demands maximum effects to be achieved with the minimum means (July 1972 CHEMTECH, pages 390-392). Accordingly, an engine, i.e. a machine converting any energy into mechanical motion, must be: (1) running fast for optimal efficiency; (2) light for holding material and transport costs, as well as inertia, centrifugal and gyroscopic forces down; and (3) simple, in order to keep manufacturing, maintenance and repair costs low, and profits high.
Of all engines, the heat engine, especially the internal combustion engine, is utilized most widely, despite its theoretical and practical shortcomings, e.g. low efficiency and torque at appropriate temperature and speed ranges. Basically, it requires a chamber of variable volume, for which the rigid, right, circular or trochoidal cylinder with movable piston is chosen most often, in spite of the high material and manufacturing costs encountered in the precision-shaping of any body with curved surface. Therefore, both vehicle engines and power-generating turbines, and even rotary engines with flexible combustion chamber according to U.S. Pat. No. 3,872,852, contain expensive, precision-shaped parts, such as cylinder blocks and turbine blades respectively.
In contrast, the heat and pumping engines described and claimed herein, contain mainly rectangular parts, all of the surfaces thereof are either plane while manufactured, or if curved, obtained by bending or non-precision stamping and stacking of a plurality of sheets. Moreover, they permit more integrated combinations of internal combustion engine and electric motor/generator, due to similarities in the design of their essential parts. Such combinations are not yet available for the more efficient hybrid (gas-electric) vehicles, e.g. those described in the July 18, 1983 Chemical & Engineering News, page 19, or U.S. Pat. Nos. 4,011,919 and 4,165,846 respectively. However, it has been proven already that even the present-state (less integrated) hybrids offer about twice the gas-mileage of conventional cars, due to the more efficient electric drive. It yields, in contrast to the gas engine, maximum torque at low speed, and regenerative charging of the batteries while braking as well.